Flagellozetes (Cosmogalumna) carinodentatus, Ermilov & Salavatulin, 2022

Ermilov, Sergey G. & Salavatulin, Vladimir M., 2022, New Species Of Flagellozetes (Cosmogalumna) (Acari, Oribatida, Galumnidae) From Vietnam, Acta Zoologica Academiae Scientiarum Hungaricae 68 (4), pp. 293-304 : 294-298

Flagellozetes (Cosmogalumna) carinodentatus sp. n.

( Figs 1 , 2 )

Diagnosis. Body length: 270–300. Pteromorph slightly striate; anogenital region and centrodorsal part of notogaster with numerous neural ridges. Lamellar line bifurcate mediobasally; anterior part of S -line dentate. Rostral and lamellar setae setiform, slightly roughened; ro/le = 1.2. Dorsosejugal and postanal porose areas present. Four pairs of rounded porose areas. Median pore absent. Lyrifissure im located between lm and A1. Epimeral setal formula: 1-0-1-1. Circumpedal carina long. Adanal lyrifissure located close and parallel to anterior part of anal plate. Leg tarsus I with 19 setae (v’ absent).

Description of adult. Measurements. Small species. Body length: 300 (holotype: female), 270–300 (six paratypes: three males and three females); notogaster width: 232 (holotype), 217–232 (paratypes). No difference between males and females in body size.

Integument ( Figs 1A–C ). Body color brown. Surface densely microfoveolate (visible only under high magnification in dissected specimens, 10 × 100). Pteromorph, basal part of prodorsum and narrow region anterior to genital aperture slightly striate. Lateral side of body partially microgranulate. Anogenital region and centrodorsal part of notogaster with numerous neural ridges (without small dense cells); ridges in anogenital region numerous and located on the entire surface (except genital and anal plates); ridges on notogaster medium numerous and occupy the area between setal alveoli lm-lm and porose areas A1-A1. Antiaxial side of leg femora I, II, IV and trochanters III, IV partially tuberculate.

Prodorsum ( Figs 1A, C ). Rostrum slightly protruding, rounded. Lamellar and sublamellar lines thin, parallel, curving backwards; L -line bifurcate mediobasally; anterior part of S -line with one row of short, distinct teeth. One pair of thin, longitudinal furrows (30) located between mediobasal parts of L -lines. Rostral (20–22) and lamellar (17–19) setae setiform, slightly roughened; le inserted between branches of L -line. Interlamellar seta (2) setiform, thin, smooth. Bothridial seta (56–60) clavate, with long stalk and shorter head rounded distally, sparsely slightly roughened. Exobothridial seta absent. Dorsosejugal porose area (12–15 × 4–6) oval, transversely oriented, located posterolateral to in. Dorsophragma distinctly elongated longitudinally.

Notogaster ( Figs 1A, C, D ). Dorsosejugal suture complete, convex medially. With 10 pairs of setal alveoli (microsetae not observed) and four pairs of rounded porose areas (Aa: 13–19; A1: 9–15; A2: 7–11; A3: 11–15); Aa located close to pteromorphal hinge, anterior to setal alveolus la. Median pore absent. Opisthonotal gland opening and all lyrifissures distinct: gla located anterolateral to A2; im between lm and A1; ip between p 1 and p 2; ips between p 2 and p 3; ih lateral to p 3.

Gnathosoma ( Figs 2A–C ). Subcapitulum size: 75–79 × 60–67; subcapitular setae (a: 15–19; m, h: 5–7) setiform, slightly roughened; a thickest; adoral seta (9–11) setiform, slightly barbed. Length of palp: 64–67; postpalpal seta (4) spiniform, smooth. Length of chelicera: 86–94; cheliceral setae (cha: 26–30; chb: 19–22) setiform, barbed.

Epimeral and lateral podosomal regions ( Figs 1B, C ). Epimeral setal formula: 1-0-1-1; all epimeral setae (3b: 11–15; 1a: 7; 4a: 4) setiform, thin, smooth. Circumpedal carina long, reaching pedotectum I.

Anogenital region ( Figs 1B–D ). Genital (g 1: 9–11; g 2: 7; g 3 – g 6: 4), aggenital (4), anal (4), and adanal (4) setae setiform, thin, smooth. Anterior edge of genital plate with three setae. Aggenital seta located between genital and anal apertures, closer to genital aperture. Adanal lyrifissure located close and parallel to anterior part of anal plate. Adanal setae ad 1 and ad 2 posterior, ad 3 lateral to anal plate; distance ad 1 – ad 2 shorter than ad 2 – ad 3. Unpaired postanal porose area (7–11 × 4–6) oval.

Legs ( Figs 2D–G ). Median claw distinctly thicker than lateral claws, all slightly roughened on dorsal side. Porose area on all femora and on trochanters III, IV present, but poorly visible. Formulas of leg setation and solenidia: I (1-4-3-4-19) [1-2-2], II (1-4-3-4-15) [1-1-2], III (1-2-1-3-15) [1-1-0], IV (1-2-2-3-12) [0-1-0]; famulus lateral to solenidion ω 1; seta v’ on tarsus I absent; s eupathidial; solenidion of tibia IV inserted in anterior part of the segment; homology of setae and solenidia indicated in Table 1 .

Material examined. Holotype (female) and two paratypes (one male and one female): Vietnam, Dong Nai Province, Dong Nai Biosphere Reserve, Cat Tien National Park , 11°25’40”N, 107°25’34”E, about 130 m a.s.l., bark from Haldina cardifolia (height: 0.5 m) (sample: 1-1), 20.06.2021 – 04.07.2021 (V. M. Salavatulin and A. A. Kudrin).

Four paratypes (two males and two females): the same as for the holotype but other tree of H. cardifolia (sample: 8-1) with coordinates 11°25’45”N, 107°25’38”E.

Type deposition. The holotype and six paratypes (preserved in 70% solution of ethanol with a drop of glycerol) are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia.

Etymology. The species name carinodentatus refers to dentate sublamellar line (carina).

Remarks. Flagellozetes (Cosmogalumna) carinodentatus sp. n. differs from all representatives of the subgenus by the presence of a row of teeth on sublamellar line. In having neural ridges on the notogaster and in anogenital region, stria on pteromorph, four pairs of notogastral porose areas, long circumpedal carina, bifurcate lamellar line, 19 setae on leg tarsus I, and in the absence of a median pore, the new species is morphologically most similar to F. (C.) sandori Ermilov et Kalúz, 2019 from Malaysia. However, the new species differs (in addition to the presence of teeth on S) from the latter by the absence (versus presence) of sparse and minute foveolae on the body and stria on the subcapitular mentum, distinctly longer lamellar setae (ro/le = 1.2 versus 1.6), the presence (versus absence) of two prodorsal furrows, and by more numerous neural ridges in anogenital region which are located on entire surface (versus mostly between genital and anal apertures).

Figures

Fig. 1. Flagellozetes (Cosmogalumna) carinodentatus sp. n., adult: A = dorsal view; B = ventral view (gnathosoma, legs and right pteromorph not shown); C = right lateral view (gnathoso- ma, legs and pteromorph); D = posterior view (part or left half not shown). Scale bar 50 μm

Fig. 2. Flagellozetes (Cosmogalumna) carinodentatus sp. n., adult: A = subcapitulum, ventral view; B = palp, left, paraxial view (femur, genu and tibia slightly turned ventral); C = chelicera, left, paraxial view; D = leg I, without trochanter, right, antiaxial view; E = leg II, without trochanter and tarsus, right, antiaxial view; F = leg III, without tarsus, left, antiaxial view; G = leg IV, left, antiaxial view. Scale bars 20 μm